And next tonight we turn to a developing story about terror threats against americans, word tonight that every american embassy across the muslim world has been ordered to close this COMING SUNDAY, AUGUST 4th. There is a new and miss serious security concern. Reporter: The threat is credible and serious. A senior u.S. Official telling abc news, there is a "specific threat, a concerted effort against a u.S. Embassy or consulate, we just don't know what the specific target is." Another u.S. Official adding, "there could be other targets, not just embassies." Beginning sunday, some of our biggest embassies will be closing. Including egypt, iraq, qatar, and kuwait. There has not been a mass closing of embassies and consulates due to an intelligence threat since the first anniversary of 9/11. Normally an ambassador would make the determination, but this time it is washington ordering the embassies to close down. Reporter: And while the closures right now are just for sunday, it may be extended as much as 10 additional days in some of those facilities as the u.S. Intelligence is working to try to get more specifics. Thank you, martha. Also from overseas tonight

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